Cummins ISX & ISB Difficult Cold Start


Several things could be causing difficult cold starts for your Cummins Semi:

Cause: Stiction

Solution: Treat the engine with the Stiction Eliminator, and run it for one full oil change interval.

Cause: Poor fuel quality

Solution: If you suspect poor fuel quality, treat with Diesel Extreme. In winter, treat with a half-dose of Diesel Extreme and a full dose of Diesel Winter Anti-Gel.

Cause: Grid heater problem

Solution: Check the grid heater


Low boost when the truck is cold could be caused by stiction in the turbo bearing. Treating with our Stiction Eliminator should clear this out. A problem with the grid heater could be something as simple as corroded battery cables, making the heater not work at full capacity, or it could be a complete failure of the grid heater.

If you have any questions, feel free to contact one of our diesel experts.


Difficult Cold Start - Heavy-Duty Cummins Symptoms
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